Joint Replacement, Limb Lengthening, Limb Deformity, & Joint Preservation

Limb Lengthening, Limb Deformity, & Joint Preservation

Many patients have never heard of limb lengthening; however, it’s very real approach to addressing limb deformities, such as bow leggedness or knock knees. Patients with short stature can also benefit from limb lengthening procedures.

Limb Length Discrepancy (different length legs) is the most common reason patients request limb lengthening procedures here at Mount Sinai and other medical centers with highly advanced orthopedic surgical capabilities. In fact, the physician of the Columbia University Orthopedics at Mount Sinai Medical Center are among only a handful of orthopedic programs in the nation to offer these complex surgeries.

Conditions & Treatment

Limb Length Discrepancy (LLD)
Limb length discrepancy is a difference between the lengths of the arms or legs. Except in extreme cases, differences in arm length do not usually impact how the arms function and do not always require treatment.

While a slight difference in leg length (<1cm) may not cause symptoms, larger differences secondary to congenital deformities, traumas, or previous surgeries can cause lower back, hip, knee and ankle pain, and imbalanced gait resulting in a limp.

Mild leg-length discrepancies may be addressed with a shoe lift. More significant differences in leg length tend to require a surgical procedure such as limb lengthening.

Knock Knees
Genu valgum, or “knock knees,” is a developmental condition that causes the knees to bend in toward one another, creating a gap between the ankles when the patient stands with their knees together. The name comes from how the knees “knock” against each other when standing or walking normally.

Knock knees frequently occur in children aged three to six, are slightly more common in girls than boys, and most often go away on their own as the child grows. If they persist after the age of eight and into adulthood, it may indicate knock-knee syndrome, a condition that places undue stress on the outward facing side of each knee, which can lead to meniscus and cartilage injury, and knee arthritis over time.

Surgery, consisting in realignment of one or both knee bones, is indicated in said cases to improve pain, improve outcomes after meniscus surgery, and ultimately delaying the onset and progression of knee arthritis. Studies have in fact observed that knee realignment surgery in already arthritic knock knees may delay the need of a knee replacement by 10-15 years.

Bowlegs
Genu varum, or “bowlegs,” is a developmental condition that causes the legs to curve outward so that the knees splay apart even when the patient stands with their feet and knees together. The name comes from how the legs “bow” outward, leaving a wide gap between the knees when the patient stands naturally.

Bowlegs are very common in infants and young children, with many babies born bowlegged in response to their folded position in the womb. Most grow out of the condition within the first two years. If the condition persists into adulthood, it may cause bowleg syndrome. This condition can cause pain on the inside part of the knee, may be responsible for meniscus tears, and can lead to knee arthritis. A times, the deformity can progress over time if untreated, causing worsening of the symptoms.

As with knock knees, there are a variety of surgical options for treating bowlegs that can improve the appearance and function of the joints, delaying the onset and progression of arthritis. Studies have in fact observed that knee realignment surgery in already arthritic bow legs may delay the need of a knee replacement by 10-15 years.

Limb Lengthening Surgery
Whether for functional purposes or cosmetic reasons, reconstructive limb lengthening limb lengthening is performed with a telescopic magnetic rod, which is inserted into the bone. The surgeon breaks the bone, and then the rod is lengthened by approximately 1mm per day. A patient can expect to increase her or his height by up to three inches with one surgery. Surgeons can repeat this procedure to double the increase to three additional inches for a total increase in height of six inches.

During a limb lengthening surgery, the highly qualified physician surgically separates the bone and distracts (pulls apart) the segments very slowly so that new bone continues to form in the gap. This is accomplished by inserting a sophisticated, new generation limb lengthening device. This device will be used to widen the gap between the two sections as the bone slowly heals and regenerates to fill in the empty space, eventually resulting in a longer leg bone.

Following distraction, the final stage of treatment is consolidation. During consolidation, the patient allows the natural healing process to continue strengthening and healing the bone and aiding the ligaments, muscles, nerves, and tendons surrounding the bone in adapting to their new physical configuration. The healing in this phase is bolstered by regular physical therapy and rehabilitation sessions, which began during the distraction phase. Lastly, the device is surgically removed after the desired length has been reached and the bone has sufficiently healed.